[PATCH 3.18 081/124] Input: yealink - validate number of endpoints before using them

[Greg Kroah-Hartman]

3.18-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Johan Hovold <jo...@kernel.org>

commit 5cc4a1a9f5c179795c8a1f2b0f4361829d6a070e upstream.

Make sure to check the number of endpoints to avoid dereferencing a
NULL-pointer should a malicious device lack endpoints.

Fixes: aca951a22a1d ("[PATCH] input-driver-yealink-P1K-usb-phone")
Signed-off-by: Johan Hovold <jo...@kernel.org>
Signed-off-by: Dmitry Torokhov <dmitry.torok...@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>

---
 drivers/input/misc/yealink.c |    4 ++++
 1 file changed, 4 insertions(+)

--- a/drivers/input/misc/yealink.c
+++ b/drivers/input/misc/yealink.c
@@ -875,6 +875,10 @@ static int usb_probe(struct usb_interfac
        int ret, pipe, i;
 
        interface = intf->cur_altsetting;
+
+       if (interface->desc.bNumEndpoints < 1)
+               return -ENODEV;
+
        endpoint = &interface->endpoint[0].desc;
        if (!usb_endpoint_is_int_in(endpoint))
                return -ENODEV;